System and method for storing and displaying data

ABSTRACT

A system and method are provided for managing a plurality of data values which define an attribute of an object. The system includes a computer having a display. The computer has a user defined database or spread sheet which stores the data values. A facility is provided for defining an arbitrary, user defined graphic representing the object; that is displayed by the computer. A region is identified within the graphic. A value is associated with the region. The value represents a visual attribute. The identified region of the graphic is linked to a data field of the database or spreadsheet. The data field stores one of the plurality of data values. A rule is applied to determine the value of the visual attribute as a function of the data value stored in the data field. The visual attribute of the region is automatically changed according to the rule when the data value changes. An exemplary system displays a graphic representing the bottom of a truck. The individual regions of the graphic represent the tires of the truck. The regions representing tires are colored as a function of tire tread depth, tire age, or both tire tread depth and tire age.

BACKGROUND OF THE INVENTION

The increasing complexity of the marketplace has made it increasingly important for business persons to assimilate large volumes of information efficiently. Business and industry are increasingly challenged to quickly and efficiently administer, record, account for and analyze the changing attributes of those things that they produce, service, maintain, market, sell and administer. Typically, the most effective method of presentating data is graphically, using pictures and charts.

Statistical analysis software programs that receive sets of input data and output histograms, pie charts and line graphs are well known. There are many business decisions for which these presentation methods do not provide the information in a form that is quickly and easily understood by the business person.

Powerful microprocessors have made user-friendly Man-Machine Interfaces (MMIs) practical. Fourth generation programming tools have been developed to facilitate the development and maintentance of software.

The InTouch™ software development toolkit by the Wonderware Corporation of Irvine, Calif., is an MMI application generator for supervisory control, monitoring and data acquisition applications in an MS Windows environment.

InTouch™ provides the capability to develop graphics which are embedded within the MMI application as "smart objects." The objects may be connected to desired data values in a spreadsheet. "Action scripts" may be invoked for "change of state" conditions, upon opening of windows, or occurrence of an alarm condition. Alarms may be assigned, causing a portion of the display to change color. In Touch uses a proprietary extension of the Data Exchange data transfer mechanism to connect spreadsheets or databases to the MMI applications.

Application software developers require additional tools for quickly and easily developing portable MMI application programs. In particular, tools are required for displaying each type of data in the format that is most easily understood. These tools must be simple enough for the developers to master quickly, but capable of producing graphical output displays having a virtually unlimited variety of formats.

The end users of these applications require the data in a format that they can readily understand. For example, the operators of trucking fleets must track large quantities of information about tires. Tire expenses are typically among the highest costs for a trucking fleet. Tire wear and age must be tracked. The number of times that an individual tire has been retread must be tracked. Repairs for each truck in the fleet that may influence tire wear should be tracked. Special repairs performed on an individual tire must be tracked. The fleet operator should be able to compare the cost effectiveness of products made by different tire manufacturers, and of different brands made by a single manufacturer. For each tire, the fleet operator should be able to predict an expected time for retreading or replacing the tire, both to schedule maintenance operations and to budget for the repair and replacement expenses. The inventors are not aware of any automated system in the prior art meeting the needs of truck fleet operators.

Fleet operators need automated tools for managing their tires. Software developers need a development toolkit that facilitates the development of such a system.

SUMMARY OF THE INVENTION

The present invention is a system and method for managing a plurality of data values which define an attribute of an object.

The system includes a computer having a display. The computer has a user defined database or spread sheet which stores the data values.

A facility is provided for defining an arbitrary, user defined graphic representing the object that is displayed by the computer.

A region is identified within the graphic. A value is associated with the region. The value represents a visual attribute.

The identified region of the graphic is linked to a data field of the database or spreadsheet. The data field stores one of the plurality of data values.

A rule is applied to determine the value of the visual attribute as a function of the one data value stored in the data field.

The visual attribute of the region is automatically changed in accordance with the rule when the one data value changes.

According to a further aspect of the invention, an application software program is provided that displays a graphic representing the bottom of a truck. The individual regions of the graphic represent the tires of the truck. The regions representing tires are colored as a function of tire tread depth, tire age, or both tire tread depth and tire age.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram of an exemplary computer system suitable for practicing the invention.

FIG. 2 is a block diagram of a software system for practicing the invention in the computer system of FIG. 1.

FIG. 3 is a flow chart diagram of an exemplary process for entering the information defining the graphic shown in FIG. 1 into the system shown in FIG. 2.

FIGS. 4A-4C show dialog boxes used for entering the information into the computer shown in FIG. 1, using the method shown in FIG. 3.

FIG. 5 is a block diagram of a file structure created by the method of FIG. 3.

FIG. 6 is a block diagram of a region data structure shown in FIG. 5.

FIG. 7 is a block diagram of a rule data structure shown in FIG. 5.

FIG. 8 shows a second exemplary embodiment of the invention implemented as a spreadsheet with region color defined by program control.

FIG. 9 is a flow chart diagram showing the application program of FIG. 1.

FIGS. 10-15 show displays containing dialog boxes, as generated by the system of FIG. 1.

FIG. 16 is a graph of tire tread depth generated by the system shown in FIG. 1.

FIGS. 17-20 show displays containing dialog boxes, as generated by the system of FIG. 1.

OVERVIEW

The present invention is a system and method for creating a relationship between a plurality of data and a graphic representing the data (which may be stored as a bitmap). When data are stored in a database, file, spreadsheet, or other format, the invention determines the graphic's appearance so as to reflect the values of the data. The invention allows software application developers and end-users to quickly add visual attributes (e.g., coloring or shading) to a graphic.

The invention is embodied in a tool for software developers, and in application programs that use the tool. The tool identifies regions within a bitmap, as well and colors in these regions. The color depends on the data in the spreadsheet or database.

FIG. 1 is a block diagram of an exemplary computer system 100 suitable for practicing the invention. The computer system 100 comprises a computer 110 having a processor 112, memory (typically including both Random Access Memory (RAM) and at least one disk drive). A database or spreadsheet 160 is stored in the memory 114. The computer system 100 also includes a display 120, and a pointing device 118, which may be a mouse (other pointing devices, such as a trackball, stylus, light pen, puck or touch screen may also be used).

FIG. 2 is a block diagram of an exemplary system 200 in accordance with the invention. The invention is a system and method for managing a plurality of data values which define an attribute of an object.

A facility 210 is provided for defining an arbitrary, user defined graphic 140 (shown in FIG. 1) that is displayed by the computer 100. The graphic 140 is stored in the form of a bitmap. This bitmap may be created with any painting or drawing application that supports bitmap (BMP) file format. Several commercially available painting software applications support this file format: e.g., "PAINTBRUSH"™ (by the MicroSoft Corporation) and "COREL DRAW"™ (by the Corel Corporation of Ottawa, Ontario, Canada) support this file format. System 200 uses a user defined bitmap from the graphic facility 210 as a starting point. In the exemplary embodiment shown in FIG. 1, the graphic 140 is a bottom view of a truck.

Throughout the description, the bitmap (BMP) file format is referenced because it is the most popular graphic file format for the Windows 3.x environment. However, the invention may also be practiced using other graphic file formats, such as Tag Image File Format (TIFF), Compuserve graphics image format (GIF), PCPaintbrush (PCX) and others.

A region utility 220 is provided for identifying a plurality of regions 142a-142j within the graphic 140. A region is any area within the bitmap that is completely enclosed by a border. The regions 142a-142j have a visual attribute, which has a value. The regions utility 220 is used to identify portions of the graphic, the visual attributes of which are determined automatically by software. In the embodiment of FIG. 1, the regions 142a-l42j are representations of tires, and the visual attribute is color. Although reference is made hereinafter to determination of the color of a region, it will be understood that other visual attributes (e.g., shade, cross hatching or apparent depth) could be defined in the same manner.

The region utility 220 is used by the software developer of the system shown in FIG. 1 to enter two type of data: (1) region data which define the locations of the regions 142a-142j within the bitmap 140; and (2) rule data, which define the database or spreadsheet 160 in which the object attributes are stored, and the criteria by which the visual attributes of the region are determined from the information in the database or spreadsheet 160.

The region utility 220 creates a graphics file structure 500 (shown in FIG. 5). When the user saves region and rule information created during a session with the region utility 220, the data are stored in a QuikLook Graphics file 230 (hereafter QLG file 230) using a format referred to as the QuikLook Graphics file format (hereafter, QLG file format). The QLG file format defines a single file structure which contains: (1) a bitmapped representation of the graphic; (2) a plurality of region data structures; and (3) a plurality of rule data structures. The region utility 220 has the ability to write and read files which are formatted according to the QLG file format. The format is described in detail below with reference to FIGS. 6 and 7.

A graphics server 240 is provided for linking the identified regions 142a-142j of the graphic 140 to respective data fields of the DBMS or spreadsheet 160. The graphic server 240 applies the rules stored in the QLG file 230 to determine the values of the visual attribute of each region 142a-142j as a function of the respective data values stored in the database or spreadsheet 160.

The graphics server 240 is used by a client application program 270 at run time to identify the value of the visual attribute of each region 142a-142j in the graphic 140, and to set the appearance of the regions. For example, in the embodiment shown in FIG. 1, the client application program 270 manages truck tire information. The client application 270 displays the graphic 140 as part of an application display screen 130. The client application program 270 calls the graphics server 240, which identifies the colors for each of the regions 142a-142j (representing tires), and paints each region an appropriate color.

According to another aspect of the invention, the client application 270 can use the graphics server 240 for modifying the identified regions of the graphic 140 interactively. The user of the client application program 270 uses a pointing device, such as a mouse 118 (shown in FIG. 1), to select one of the regions 142a-142j. The selected region of the graphic 140 is then dragged to a predetermined field 150, 151 or 152 within the display 130, and dropped in the predetermined field. Responsive to the drag and drop events, a corresponding value stored in the database 160 is modified.

For example, in the exemplary application program, a dialog box is displayed, into which a user inputs data describing a change in status of the object represented by the region that has been dropped. A message is automatically transmitted to the database, identifying the change in status.

The invention provides a component-based software application that may be utilized by many different types of computer users, from end-users of commercial off-the-shelf DBMSs and spreadsheet programs to software application developers. Developers can easily use a toolkit in accordance with the invention in their application development efforts. End-users can easily use the invention to display spreadsheet data in a more easy-to-understand format.

The end-user of an application program according to the invention can gain an understanding of the objects in the database while viewing the attributes which change with the passage of time, change in status, or other variable. In addition, the graphic representing the objects is automatically updated as the underlying variable (time, status, etc.) changes.

DETAILED DESCRIPTION Software Development Tool

FIG. 3 is a flow chart diagram of an exemplary method for developing an application using a development tool according to the invention. FIGS. 4A-4C are exemplary screens displayed by the tool during development.

In FIG. 3, at step 302, the developer determines what database or spreadsheet to use. In the exemplary embodiment, a database is used. If a database is used, it is preferable to use a database management system (DBMS) for which an Open Database Connectivity (ODBC) driver has been developed. The ODBC interface is specified in "ODBC Technical Overview", Microsoft Technet CD, 1992, which is expressly incorporated by reference herein for its teachings on an interface for portable database application development.

At step 304, the developer creates the graphic in the form of a bitmap.

At step 306, the developer initiates the region identifier utility 220 (shown in FIG. 2). This action causes the region utility window 400 (shown in FIG. 4A) to be displayed.

At step 308, the developer selects the BMP button 402 (FIG. 4A) with the pointing device 118. A file selection dialog box (not shown) displays all of the bitmap files in the current directory, from which the bitmap is selected from storage. The graphic 404 is displayed. In FIG. 4A, the graphic 404 is a bottom view of a truck trailer.

At step 310 (FIG. 3), the developer initiates the region identifier tool by selecting the "Create" button 406 (FIG. 4A). The system is now prepared for identification of regions.

At step 312 (FIG. 3), the developer selects a region 408 (FIG. 4A) by clicking the mouse within the region 408. A small region indicator 410 (which may be a square box) is displayed within the selected region 408. The developer continues selecting regions as desired.

At step 314 (FIG. 3), the developer clicks on the "Select" button 412 (FIG. 4A). Hereafter, the terms "select" and "click on" are used interchangeably. (One of ordinary skill in the art will recognize that, although the term "click" best describes selection using a mouse, selection via other pointing devices is also contemplated within the scope of the invention). The developer then clicks on one of the region indicators 410.

FIG. 4B shows the region indicator dialog box 430 that is displayed when the "Select" button 412 is selected in step 314 (FIG. 3). The dialog box 430 includes a region identifier (ID) 432, an indication of the color of the border of the region, and a plurality of position coordinates 436 and 438 defining a location of a point in the region. In the exemplary embodiment, the plurality of position coordinates define the location of the upper left corner of the region indicator 410 relative to a corner of the bitmap 404. The X and Y coordinates 436 and 438 are displayed, and may be edited by the developer. The developer also enters the region ID 432 and the border color 434, and selects the "OK" button 440. The developer continues to select region indicators until data have been entered for each region.

At step 316 (FIG. 3), when all of the region data are created, the developer may select the "Data" button 414 (FIG. 4A) to enter rule data.

FIG. 4C shows the rule data dialog box 450 that is displayed in step 316. Each graphic 404 may be associated with one or more rules. A rule may be used to define the colors of all of the identified regions 408 in the graphic 404.

A rule identifier (ID) is entered in the rule field 452. The name of the variable in the database query is entered in the argument field 454. The "type" of the variable in argument field 454 is entered in the "argument type" field 456. One or more arguments may be entered. The name of the database in which the data that define the objects are stored is entered. The database query (which may be written in Structured Query Language, SQL) is entered in the SQL field 460. Each region of the graphic corresponds to a respective entry in the region ID column of a table in the database. In field 458, the name of the variable in the SQL statement 460 (and in the database) that corresponds to the region ID (FIG. 4B) is entered in Region ID field 462. The rule that is used to determine the color of a region 408 based on the results of the query is entered in rule field 464.

A given application program may include one or more rules for a particular graphic. Only one of the rules is applied at any given time to color the regions. For example, in FIG. 1, the status box 156 allows the end user of the application to select one of the following three criteria: (1) "depth" 156a, (2) "age" 156b or (3) "depth and age" 156c. The application is programmed so that selecting any of these three criteria 156a-156c results in the use of a respectively different rule. For example, when "depth" 156a is selected (as shown), then the rule "Tread Depth" shown in FIG. 4C is used.

The Data/Rule dialog box 450 allows the developer to specify many rules. To move through rules already stored for a particular bitmap, the developer selects the "PREV" button 466 (to move to a previous data/rule) or the "NEXT" button 468 (to move to the next rule). To delete a rule, the developer selects the "DELETE" button 470. To add a new rule the developer selects the "PREV" button 466 or the "NEXT" button 468 until a blank form 450 is reached.

The specific rule information shown in FIG. 4C is described below with reference to an exemplary application program in accordance with the invention. This program is a system for managing truck tire data.

FIG. 4A shows additional controls that may be used to modify region data that have already been created. An "erase" button 416 is selected to erase (remove) a region indicator 410 that has already been created. When a region is "erased", it is no longer colored according to the rule at run time.

A "move" button 418 allows the developer to move a region indicator 410 to a new location, so that a different portion of the graphic is colored in accordance with the rule. Also, the "move" button 418 may be used to adjust the position of the region indicator within the region in which it is currently placed.

At step 318 (FIG. 3), when the "Save" command is selected from the "File" menu 420, the region and rule data created in steps 312-316 are saved in a Quicklook Graphics (QLG) file structure 500 (shown in FIG. 5). This file is used by the Graphics OLE server 240 (shown in FIG. 2).

Using the "Open" command from the "File" menu 420 (FIG. 4), the developer can open an existing QLG file 500 (shown in FIG. 5) that was created during an earlier session with the region utility 220. The region utility 220 retrieves all information stored in the file 500. The developer can then modify and manipulate the identified regions and save the changes.

QLG FILE STRUCTURE

FIG. 5 is a block diagram of a QLG file 500. The file structure 500 includes all the information needed to define the graphic to an application program. A bitmap size field 502 specifies the size of the bitmap of the graphic. The bitmap data are stored in a field 504. The number of regions defined in steps 312 and 314 (FIG. 3) are specified in a field 506. The region data for each region are stored, individually, in region data structures 510a-510n. After the last region 510n, the number of rules appears in a field 515. A rule data structure 520a-520m is provided for each rule used to color the graphic 404. If more than one rule is entered for a graphic, there is a respective rule data structure for each rule 520a-520m.

FIG. 6 is a block diagram of one of the region data structures 510a shown in FIG. 5. The other region data structures 510b-510n have the same components as the data structure 510a, and are not described separately herein. Data structure 510a (FIG. 6) includes a region ID field 610 for storing the region ID entered in field 432 (FIG. 4B) of the region dialog box 430. A border color field 620 (FIG. 6) stores the border color entered in field 434 (FIG. 4B). An X coordinate field 630 stores the X coordinate entered in field 436 (FIG. 4B). A Y coordinate field 640 stores the Y coordinate entered in field 438 (FIG. 4B).

The Region data structure 510a may be defined using the following statements:

    ______________________________________                                         #define MAXREGIONS 1000                                                        struct stRegion{                                                                 char * id;  //string to identify the region -                                  ID in the region information dialog box                                        long bordercolor; //border color of the region                                 long xpos; //x position of region identifier                                   long ypos; //y position of region identifier                                 } tyRegion;                                                                    tyRegion aRegion[1:MAXREGIONS]; //an array of regions                          ______________________________________                                    

Each time a region is identified by the developer, an entry into a region data structure 510a is made. The descriptor aRegion indicates an array of regions. An example of an entry in aRegion is:

    ______________________________________                                                  aRegion[1].id = "pos1"                                                         aRegion[1].bordercolor = 255                                                   aRegion[1].xpos=535                                                            aRegion[1].ypos=273                                                   ______________________________________                                    

The entries in this data structure are maintained and manipulated by the user through the toolbar actions of Select, Create, Erase, and Move.

FIG. 7 is a block diagram of the rule data structure 520a shown in FIG. 5. Data structure 520a (FIG. 7) includes a rule ID field 710 for storing the rule ID entered in the rule ID field 452 of the rule dialog box 450 (shown in FIG. 4C). An argument field 720 stores the name of one or more arguments (entered in field 454 of FIG. 4C) that are used to query the database. An argument type field 730 (FIG. 7) stores the type of the argument stored in field 720 (entered in field 456 of dialog box 450). A database field 740 stores the name of the database entered in the database field 458 of dialog box 450 (FIG. 4C). The SQL field 750 (FIG. 7) stores the database query entered in field 460 of dialog box 450 (FIG. 4C). The regionid field 760 (FIG. 7) stores the name of the region ID variable used in the SQL statement in field 460 of dialog box 450 (FIG. 4C). The rule field 770 (FIG. 7) stores the rule entered in the rule field 464 of dialog box 450 (FIG. 4C). The rule may be written in the same language as the application program. For example, in the exemplary embodiment, the rule is written in PowerBuilder PowerScript syntax.

The rules are stored in the following data structure.

    ______________________________________                                         #DEFINE MAXRULES 100                                                           struct stRule {                                                                  char * ruleid; //string identifing the rule name                               char * argument; //coma delimited string identifing                              arguments ie arg1;arg2;arg3;                                                 char *argumenttype; //coma delimited string                                      identifying argument types                                                     number;string;number;                                                        char * database; //string identifing the database                              char * sql; //the sql statement                                                char * regionid; //column to use as region                                       identifier                                                                   char * rule; //the rule                                                      } tyRule                                                                       tyRule aRule[1:MAXRULES]; //array of rules                                     ______________________________________                                    

GRAPHICS SERVER SOFTWARE ARCHITECTURE

The exemplary software development toolkit according to the invention uses Object Linking and Embedding (OLE) 2.0 technology as described in OLE Custom Controls Backgrounder (C) 1992-1995 MicroSoft Corporation, which is expressly incorporated by reference herein for its teachings on developing embedded controls. The exemplary system is implemented as an OLE 2.0 custom control.

The exemplary software system 200 (FIG. 2) was developed using MicroSoft Visual C++ and compiled as an OLE 2.0 capable application. The system may be used in any environment supporting OLE 2.0 custom controls and applications.

An OLE Custom Control is an embeddable object with in-place activation capabilities. To be "embeddable" means that a control is capable of being placed inside another application. "In-place activation" means that the application inside of which the control is placed can modify or use the control.

A custom control has three sets of attributes: properties, events, and methods, as defined in OLE Custom Controls Backgrounder. Properties are named characteristics or values of the control such as color, text, number, or font. Events are actions triggered by the control in response to some external action on the control, such as clicking a mouse button. Methods allow external code to manipulate the object's appearance, behavior, or properties.

Events supported by the graphics server 240 include RegionClick, RegionDoubleCLick, RegionDrag, and RegionDrop.

Events are used by MicroSoft Windows objects to detect that something (i.e., mouse click, mouse move) has happened. An application program may respond to these events. For example, the OLE 2.0 graphics server 240 (FIG. 2) may send information back by setting the event message parameters. Events, event messages, Click, Double Click, Drag, and Drop are part of the technology of Windows. The following events are supported by the graphics server 240 (FIG. 2).

When the mouse button is clicked on a region identifier, the graphics OLE 2.0 server 240 responds with a RegionClick event. The message string parameter of the message sent by the graphics server 240 is set to the string 432 (FIG. 4A) identifying the region 408.

When the mouse button is doubledclicked on a region identifier 410, the graphic OLE 2.0 server responds with a RegionDoubleClick event. The message string parameter of the message sent by the graphics server 240 is set to the string 432 (FIG. 4A) identifying the region 408.

The dragging of a region 408 starts a RegionDrag event and sets the message string parameter of the message sent by the graphics server 240 to the string 432 identifying the region 408.

A RegionDrop event identifies that a software object has been dropped on a region (e.g., retread region 151 in FIG. 1). The message string parameter of the message sent by the graphics server 240 is set to the string identifying the region 151.

Methods supported by the graphics server 240 include QLGraphicFile, QLShowRegions, QLRegions, QLAddRegion, QLDeleteRegion, QLRegionColor, QLPaintRegion and QLDataSource. Each method returns the value logic TRUE if successful; otherwise the method returns the value logic FALSE.

The QLGraphicFile method accepts a string identifying the QLG file 500 (FIG. 5) as a parameter. The QLGraphicFile method displays the bitmap portion 504 of the QLG file 500 in a picture container 141 (FIG. 1). This creates a view of the graphic 140 within an application program window 130, as shown in FIG. 1 or FIG. 8.

The QLShowRegions method accepts a boolean as a parameter. When the value of the boolean parameter is logic TRUE, the system 100 (FIG. 1) displays all the region identifiers 144. When the boolean parameter is FALSE the systen 100 removes the region identifiers 144 from view. This allows the programmer to determine whether the region identifiers are displayed to the end-user.

The QLRegions method accepts the nRegions value (in field 506 of QLG file 500, FIG. 5) and the aRegion structure 510a-510n as a parameter. The QLRegions method returns the number of regions defined in the current QLG file 500 in the nRegions field 506 and the region information in the aRegion structures 510a-510n to the application program 270. This allows the application program 270 to use the region information for any of the application's computations.

The QLAddRegion method gives the developer the ability to add regions at run-time. QLAddRegion accepts a tyRegion parameter (described above with reference to FIG. 6) and adds this new region to the internal aRegion structure 510a-510n.

The QLDeleteRegion method gives the developer the ability to delete regions at run-time. QLDeleteRegion accepts a string parameter identifying the region and removes this identified region from the internal aRegion structure 510a-510n. Thus, QLAddRegion and QLDeleteRegion allow the developer to use conditions determined at run-time to dynamically select a subset of the plurality of regions for which the value of the visual attribute is determined using the rule (i.e., to dynamically select which parts of the graphic 140 are colored).

QLRegionColor returns the current color of a region. QLRegionColor accepts a string parameter identifying the region for which the color is provided.

QLPaintRegion paints a region a specified color. QLPaintRegion accepts a string parameter identifying the region which is to be painted and a color parameter indicating the color to be used. To paint a region, the QLPaintRegion method uses a Microsoft Windows 3.X application program interface (API) call to the FloodFill() function.

The QLDataSource() method uses the database, SQL statement, and rules identified by the Region Utility in the dialog boxes of FIGS. 4A-4C. This method attaches to the database 160 (FIG. 2) and runs the SQL statement through ODBC. ODBC retrieves the data from the database and sends back the results to the QLDataSource method. QLDataSource loops through the results set and, for each regionid, applies the region's rule to the region's data to determine a color, then calls QLPaintRegion to color the region the determined color.

To specify a rule to use, the application program passes the rule name and any arguments to QLDataSource().

In the example of calling the rule entered in FIG. 4C, the application program calls QLDataSource in the following way: QLDataSource ("Tread Depth", "34") (Use rule "Tread Depth" and pass in vehicle id "34" as an argument).

After the color rules are assigned to a region, the graphics server 240 is directly attached to a database table that contains data for regions 510a-510n and rules 520a-520m. The graphics server 240 uses the data about the region and the rule to color in the regions 142a-142j (FIG. 1) of the graphic 140. The QLDataSource method uses ODBC to attach to the database 160 and retrieve data from the database. The region utility 220 allows the developer to specify the database 160, SQL statement 460 (FIG. 4C), and rules 464. This information is stored in the QLG file.

As described above with reference to FIG. 4C, the exemplary system uses underlying data stored in a database and accessed by issuing SQL statements 460 through ODBC. The invention may also use underlying data stored in a spreadsheet. One of ordinary skill in the art can readily write spreadsheet queries using the native macro language of the spreadsheet program. A rule data structure suitable for use in conjunction with a spreadsheet is the same as the rule data structure 450 shown in FIG. 4C, except that the SQL statements 460 are replaced by spreadsheet macro language commands. Thus the same software development toolkit may be used regardless of whether the underlying data is to be stored in a database or spreadsheet.

FIG. 8 is an example of an exemplary embodiment of a spreadsheet application 800 in accordance with the invention. Spreadsheet 800 includes the graphic 140 embedded within a cell. The graphic 140 is embedded as an OLE 2.0 custom control, similar to the exemplary custom control embedded in a database program. Special functions in the application program may be implemented using the spreadsheet macro language, and the controls may be placed on the toolbar 802.

One of ordinary skill in the art will recognize that both the database and spreadsheet applications of the invention have their own advantages. Applications developed for use with underlying databases may have greater portability between database management systems through compliance with the standard ODBC interfaces. The applications are developed to comply with the ODBC client interface. The application may then be ported over to interface with any database that uses any DBMS for which an ODBC driver has already been developed (e.g., Microsoft Access). Any ODBC client can access any DBMS for which there is an ODBC driver.

On the other hand, those who are familiar with a given spreadsheet program may find it more convenient to program in the native macro language of the spreadsheet.

VEHICLE STATUS APPLICATION PROGRAM

The development tool according to the invention may be used to develop application programs quickly and easily, in which data are displayed graphically, and the colors of individual regions of the graphic are used to convey information at a glance.

Referring again to FIG. 1, the first exemplary application program is the Vehicle Status application program 100, for tracking truck tire information. Truck tire costs are among the largest costs in maintaining a trucking fleet. The Vehicle Status program provides comprehensive tire data tracking for an entire fleet. The Vehicle Status program has the following important features:

(1) A graphic 140 depicting a truck is shown in a format that is easily recognizable. The individual tires 142a-142j are shown, and color coded to indicate the status of the tire. For example, tires 142a and 142i are green, tires 142b and 142c are blue, tires 142d and 142e are yellow, and tire 1429 is red. In the example, good tires are colored green or blue. Yellow indicates caution; i.e., remedial action will soon be needed. Red indicates that threre is something wrong with the tire requiring immediate action (for example, the age of the tire may be above the maximum allowed age).

(2) The regions 142a-142j of the graphic 140 may be colored by applying any of a plurality of rules. The status bar 156 allows the end user to color the tires using either (a) tire tread depth, (b) tire age, or (c) both tread depth and age as criteria. For each criterion that is available to the end-user, a respective rule data structure is included in the QLG file 500 corresponding to the graphic 140.

(3) The end-user can easily and intuitively change the status of one of the tires 142a-142j by dragging and dropping the region representing the tire to one of the three control buttons 150, 151 or 152 on the left size of the display.

Using the application development toolkit described above, a programmer could develop the Vehicle Status application quickly and easily, as described below. Referring again to FIG. 4C, an example of a rule data structure suitable for use in the Vehicle Status application is shown. In the example of FIG. 4C, the rule ID 452 is "Tread Depth." In this case one argument 454, "vehicle₋₋ id", is declared. The argument type 456 of the "vehicle₋₋ id" argument is "string" The database "vehicle.db" is specified in the database field 458.

The SQL statement "select tire₋₋ pos₋₋ n, tread₋₋ depth from tire where vehicle₋₋ id=:vehicle₋₋ id" is entered in field 460. When a vehicle is selected (as described below with reference to FIG. 10), this SQL statement is used to query the tire position and tread depth attributes for each tire of the vehicle which has as a name the value of the vehicle₋₋ id argument, within the database called "vehicle.db."

The data in the database are stored in a "regionid, data" format. For example, there may be a table that has the fields, Tire₋₋ pos₋₋ n and Tread₋₋ Depth with the entries listed in Table 1.

                  TABLE 1                                                          ______________________________________                                         Tire.sub.-- pos.sub.-- n                                                                            Tread.sub.-- Depth                                        ______________________________________                                         1                    11                                                        2                    6                                                         3                    7                                                         4                    2                                                         ______________________________________                                    

The SQL statement in field 460 retrieves a regionid and a datum (in this case tire₋₋ pos₋₋ n, tread₋₋ depth). The sql statement would return the data in Table 1.

In region ID field 462, the tire₋₋ pos₋₋ n column is identified as contining the region identifier in the Region ID field 432 of dialog box 430 (FIG. 4B).

The rule declared in the Rule edit field 464 (FIG. 4C) defines the region color to be GREEN if the tread depth is greater than 10/32 inches, YELLOW if the tread depth is greater than 6/32 and less than 10/32, and RED otherwise. (Colors such as RED, BLUE, GREEN, BLACK are predefined; the user may also specify colors using the coordinates to specify a specific color to paint a region, such as RGB(x,y,z) where x is the amount of RED to use (value 0-255) , y is the amount of GREEN to use (value 0-255), and z is the amount of BLUE to use (0-255)). Other coordinates (e.g., hue, saturation and luminence) may also be used.

In this example the regions are painted the colors listed in Table

                  TABLE 2                                                          ______________________________________                                         Tire.sub.-- ID                                                                               Tread.sub.-- Depth                                                                           Color                                              ______________________________________                                         1             11            GREEN                                              2             6             RED                                                3             7             YELLOW                                             4             2             RED                                                ______________________________________                                    

One of ordinary skill in the art of programming could readily develop a similar rule for defining the tire color as a function of tire age, and a further rule for defining the color as a function of both age and tread depth. In the Vehicle Status application shown in FIG. 1, the "status" field 156 is used by the end user to select one of these rules. Within the application program software, the parameter 156a-156c selected by the end user is used by the QLDataSource method to determine which rule data structure 520a-520n is applied by the application to color the regions.

The operation of the Vehicle Status application is now described in detail with reference to FIGS. 1 and 9.

At step 900, the end-user initiates the vehicle status program. The toolbar 148 is displayed on the left side of the application window. By selecting the vehicle button 153, the vehicle dialog box 1000 (shown in FIG. 10) is invoked.

FIG. 10 shows the dialog box which contains information describing each truck in the database 160 (FIG. 1). One of the vehicles is selected by selecting one of the lines 1004 in the dialog box, and selecting the graphic tab 158. This causes execution of step 901 (FIG. 9).

At step 901 (FIG. 9) the Vehicle Status program 100 initializes the Graphics OLE 2.0 Server 240 (FIG. 2) by calling the QLGraphicsFile() method, described above. The server 240 is initialized. Once initialized, the server issues event messages from the RegionClick, RegionDoubleClick, RegionDrag and RegionDrop events, and the QLGraphicFile, QLShowRegions, QLRegions, QLAddRegion, QLDeleteRegion, QLRegionColor, QLPaintRegion and QLDataSource methods are available for use by the application program.

At step 902 (FIG. 9), the graphic 140 (FIG. 1) in the QLG file 500 (FIG. 5) is displayed in a picture container 141 (FIG. 1).

At step 904, the vehicle status application initiates the QLDataSource method.

At step 906, the QLDataSource method attaches the database 160 (FIG. 1).

At step 908, the QLdataSource method passes the SQL query 750 (FIG. 7) to ODBC 250 (FIG. 2).

At step 910, ODBC 250 retrieves the data from the database 160 and returns the data to QLDataSource.

At step 912, QLDataSource applies rule 770 (FIG. 7) to determine the color to paint a region.

At step 916, QLDataSource calls the QLPaintRegion method, which paints a region a specified color.

At step 917, steps 912 and 916 are repeated for each additional region.

At step 918, all of the regions are now displayed with the appropriate colors.

At step 920, the end-user begins to modify the data by selecting one of the regions 142a-142j which represents a tire.

At step 922, the end-user drags the region repesenting a tire over to one of the three control fields, 150-152.

At step 924, the tire is dropped in the inventory control field 150 if the user wishes to place a tire into inventory. The region drag event generates an internal message that identifies the dragged region (tire), and the region drop event generates a message that identifies the control field 150 into which the tire is dropped. Step 926 is then executed.

FIG. 11 shows the dialog box 1100 that the program displays at step 926 when the tire is dropped in the inventory control field 150 at step 924. The user then fills out the building edit box 1102 and location edit box 1104 and selects the "OK" button 1106. The database is modified to reflect that the tire has been removed from the vehicle and placed into the tire inventory. The tire is removed from a vehicle table of the database and placed in an inventory table.

At step 928 (FIG. 9), the tire is dropped in the retread/repair control field 151, if the user wishes to have the tire retreaded. Step 930 is then executed.

FIG. 12 shows the dialog box that is displayed at step 930. The end-user then fills out the edit boxes. The data in this box are particularly important for cost control purposes in the trucking industry. Field 1202 is used to identify how many times a given tire has been retread (Typically, a tire can only be retread three times). Fields 1204, 1206, and 1208 are used to identify who has performed the retread work, what repairs have been done, and what (if any) damage had been incurred for which a repair is initiated. Field 1212 is used to maintain cost information. Once the dialog box 1200 is completed, the database is updated to reflect that the tire has been removed from the vehicle and has been sent for retread/repair. Tires sent for retread/repair are stored in a separate table in the database.

At step 932 (FIG. 9), the tire is dropped in the recycle control field 152, if the user wishes to recycle the tire. Step 934 is then executed.

FIG. 13 shows a dialog box 1300 that is displayed at step 934. The end-user fills out the boxes 1301-1307. This dialog box captures information related to salvage costs of tires. Once dialog box 1300 is completed, the database 160 is updated to reflect that the tire has been removed from the vehicle and has been recycled. Recycled tires are identified in a separate table in the database.

At step 936 (FIG. 9), if the end-user tries to drop the region (tire) in a field other than fields 150-152, an error is indicated. For example, if the user drags the tire onto the vehicle information field 153 or the tire information field 154, the shape of the cursor changes to indicate that the user cannot drop the tire in either of these fields.

One of ordinary skill in the art of Windows programming could readily develop application code to initiate the dialog boxes shown in FIGS. 11-15 and 17-20 in response to the messages generated by the RegionClick, RegionDoubleClick, RegionDrag and RegionDrop events.

FIG. 14 shows a dialog box that is used to select a tire from inventory and transfer the tire to a vehicle. If a white (uncolored) region 142f, 142h or 142j is selected (as opposed to dropping a tire region on the field 150), dialog box 1400 is displayed. The attributes of each tire in the database inventory table are displayed in dialog box 1400. The user selects one of the tires from dialog box 1400. The tire is then added to the vehicle record and removed from the inventory table in the database 160. The region 142f, 142h or 142j is then colored according to the same rule used for the other tires.

FIG. 15 shows a screen 1500 that is displayed if one of the colored tire regions is selected using the right button of the mouse. The tire attributes 1502, mileage 1504, and wear history 1506 are displayed. Typically, this information is updated by using the "Add" button to add a new wear history entry to the database. This automatically changes the color of the tire in the graphic shown in FIG. 1 to reflect the latest tread depth information. If the forecast tab 1510 is selected from screen 1500, then a forecast screen 1600 (FIG. 16) is displayed. FIG. 16 shows a graph of tire tread depth plotted against mileage, which may be displayed by the forecast method.

FIG. 17 shows a screen 1700 that is displayed if the information tab 157 is selected after the vehicle button 153 is selected and a truck is selected from dialog box 1002 (FIG. 10). Screen 1700 (FIG. 17) provides a view into the database 160 showing general information about the selected truck.

FIG. 18 shows a further screen 1800 that is displayed if the maintenance tab 159 is selected after the vehicle button 153 is selected and a truck is selected from dialog box 1002 (FIG. 10). Screen 1800 provides a view into the database 180 showing the repair history of the selected truck. The repair table of the database is particularly useful for storing data that may be relevant to tire wear. For example, the selected maintenance record for this truck shows that one of the axles had been damaged.

Thus far, the description of the vehicle status application has focused on the vehicle information displayed when the vehicle button 153 is selected. The other control buttons 150-152 or 154 may also be selected immediately upon entering the program, without going through the vehicle data.

FIG. 19 shows a screen 1900 that is used to enter a new tire in inventory or transfer a tire from inventory to retread/repair or recycling. Screen 1900 is displayed if the inventory field 150 is selected (as opposed to dropping a tire region on the field 150). The end-user can scroll through the existing tires in the inventory dialog box 1902. Any of the controls 1904-1912 may be used to modify the data in the inventory table of the database. A new tire is added with the add button 1904. An incorrect entry may be deleted with the delete button 1906. An old record may be updated and saved with the save button 1908. Buttons 1910 and 1912 are used to remove a tire from the inventory table for retreading and recycling, respectively.

FIG. 20 shows a screen 2000 that is used to transfer a tire from the retread table of the database to the inventory table, or to update the data in the retread table. In particular, a tire in the retread table may be selected from dialog box 2002, and returned to the inventory table by selecting button 2008. Screen 2000 is displayed if the retread button 151 is selected directly upon initiating the application program.

The reports button 154 (FIG. 1) may be used to intitiate generation of a variety of printed reports.

Other variations of the vehicle status application are contemplated. For example, the rule may color the tires according to tread depth and tire position. For example, the wheels that are used for steering may be colored red at a slightly greater tread depth than the other wheels, so that an extra margin of safety is provided.

The rule may also color tires differently based on the manufacturer or model. If age is used to determine color, then low quality tires may be colored red at a younger age than high quality tires.

OTHER APPLICATIONS

One of ordinary skill in the art can readily apply a software development toolkit (shown in FIG. 2) according to the invention to develop other application programs which apply rules to dynamically update the colors of selected regions in arbitrary, user defined graphics.

EXAMPLE 1

For example, a manufacturer may use an application program developed using the invention to track sales throughout the USA. The manufacturer needs to track revenue and profits throughout the country. The application may display a bitmapped image of the USA (not shown), with the country derided into regions (e.g., Northeast, South, Central, and West). The invention may be used to quickly establish the "health" of sales revenues in each sales region. Unlike the tires 142a-142j in exemplary graphic 140 (FIG. 1), a graphic depicting the USA is not formed of simple rectangles. The invention may be used to color any region having a closed border, including arbitrary polygons having an arbitrary number of sides and angles. The only requirement is that the graphic be a bitmap.

A toolkit according to the invention makes it particularly simple to develop a hierarchial set of displays for sales, so that an end user can view successively smaller sales regions. Each region is associated with a graphic. When the user indicates that he or she wishes to see one of the regions broken down into a plurality of smaller regions (e.g., by double clicking on the region), the graphic associated with that region is displayed. Each graphic has its own QLG file structure.

For example, by double clicking on the Northeast region within the map of the USA, a graphic associated with the Northeast region (which may have a region for each respective one of the Northeastern states of the USA) is displayed. In the graphic of the Northeastern states, each individual state may be a separately colored region. To achieve this capability, the sales tracking application has a data structure which links each region to a respective graphic. When a RegionDoubleClick event is detected, and the event message of the RegionDoubleClick event specifies the region, the application calls up the graphic associated with the region by calling the QLGraphicFile method, specifying that appropriate file for the selected region.

The hierarchy may have an arbitrary number of levels. For example, to display sales for each county in Pennsylvania, the region representing Pennsylvania may be associated with a graphic which has a region for each respective county in the state. Further levels including cities may optionally be added.

An alternative embodiment of the development tool may make programming a hierarchical level of graphics even easier to achieve. An alternative embodiment of the region data structures 510a-510n of FIG. 5 may include a pointer to another QLG file that is associated with the region. In this alternative embodiment, an additional method would be added to return the name of the QLG file associated with a region. Then a call would be made to the QLGraphicFile method to display the region.

EXAMPLE 2

Another example of an application program developed using a toolkit according to the invention is an application suitable for use by a real estate developer, bank officer, real estate attorney, realtor, government entity (Township, state, Federal Deposit Insurance Corporation (FDIC), Office of Thrift Supervision (OTS) or regulator), engineer or site inspector, bank, real estate company, or other party who has an interest in the administration of development, regulator or maintenance of a dwelling or building.

The above-identified users need to track whether each lot is sold, whether the mortgage on each sold lot has been approved, and the status of construction on the lot. The invention may be used to display a graphic showing the construction site (plat) with a respectively different region representing each building lot (The region may represent the shape of the lot). The colors represents the status of each site. Blue may indicate that settlement on the building has occurred; green may indicate that the building is built and is ready for settlement; violet may indicate that an agreement of sale has been executed and the mortgage approved; yellow hay indicate that the mortgage has not been approved, and red may be used to indicate that no agreement of sale for the property been executed. Color may also be used to indicate whether sales, construction, etc. are behind sheduled completion or originally anticipated sales projections. The system automatically changes the colors to indicate that a sale, loan or building project is behind shedule.

Other attributes may be indicated by a visual attribute, such as color. For example, color may be used to indicate whether a house is being built as a model or "spec" house, or whether the building is being built with proceeds from a construction loan. If the building is being built with proceeds from a construction loan, color may indicate an attribute identifying the amount of money released or disbursed by the financial institution to the developer as regulated by a draw schedule agreement. Color may also be used to indicate whether the site is adequately protected by insurance. After completion of the sale, color may be used to indicate release of all liens affecting the property.

This information may be used by Internal loan review officiers and administrators, internal auditing and senior management. This example of the invention may also be very useful to FDIC, OTS or Dept. of Banking, or any other state or Federal regulatory entity charged with the supervision or periodic review of a lending institution's loan portforlio.

Although the invention has been described with reference to exemplary embodiments, it is not limited thereto. Rather, the appended claims should be construed to include other variants and embodiments of the invention which may be made by those skilled in the art without departing from the true spirit and scope of the present invention. 

What is claimed:
 1. A system for managing a plurality of data values which define an attribute of an object, comprising:a computer having a display and including a user defined database or spread sheet which stores the data values; means for defining an arbitrary, user defined graphic representing the object that is displayed by the computer; means for identifying a region within the graphic, and for associating a value with the region, the value representing a visual attribute, wherein the region identifying means include a region data structure for the region, the region data structure comprising:a region identifier, a value of the visual attribute at a border of the region, and a plurality of position coordinates defining a location of a point in the region; means for linking the identified region of the graphic to a data field of the database or spreadsheet, the data field having one of the plurality of data values stored therein; means for applying a rule to determine the value of the visual attribute as a function of the one data value, stored in the data field; and means for automatically changing the visual attribute of the region in accordance with the rule when the one data value changes.
 2. A system according to claim 1, wherein:the graphic defining means includes means for forming the graphic in the form of a bitmap, and the plurality of position coordinates define a corner of the region as a location in the graphic relative to a corner of the bitmap.
 3. A system according to claim 1, wherein the database includes an entry representing an age of the object, and the rule applying means include means for determining the value of the visual attribute as a function of the age of the object.
 4. A system according to claim 3, wherein:the object is a tire of the truck, the tire has a tread depth, and the rule applying means include means for determining the color of the region as a function of both the tread depth and the age of the tire.
 5. A system according to claim 1, whereinthe graphic is an image of a truck, the object is a tire of the truck, the region is a representation of the tire, and the visual attribute is a color of the region.
 6. A system according to claim 5, wherein:the tire has a tire tread depth, the database includes an entry representing the tire tread depth, and the rule applying means include means for determining the color of the region as a function of the tire tread depth.
 7. A system according to claim 5, wherein:the database includes an entry representing an age of the tire, and the rule applying means include means for determining the color of the region as a function of the age of the tire.
 8. A system for managing a plurality of data values which define an attribute of an object, comprising:a computer having a display and including a user defined database or spread sheet which stores the data values; means for defining an arbitrary, user defined graphic representing the object that is displayed by the computer; means for identifying a region within the graphic, and for associating a value with the region, the value representing a visual attribute; means for linking the identified region of the graphic to a data field of the database or spreadsheet, the data field having one of the plurality of data values stored therein; means for applying a rule to determine the value of the visual attribute as a function of the one data value stored in the data field, wherein the rule applying means includes a rule data structure comprising:a rule identifier of the rule, at least one argument having a value, a value which defines the argument by type, an identifier of a database in which the plurality of data are stored, a query that is used to retrieve the one data value from the database for use as the value of the argument, and the rule, wherein the rule defines the value of the visual attribute as a function of the value of the argument, and means for automatically changing the visual attribute of the region in accordance with the rule when the one data value changes.
 9. A system according to claim 8, wherein the region identifying means includes a region data structure for the region that stores:a region identifier, and a plurality of position coordinates defining a location of a point in the region.
 10. A system according to claim 9 further comprising a single file structure which contains:image data representing the graphic; a plurality of region data structures, the region data structure being included in the plurality of region data structures; and a plurality of rule data structures, the rule data structure being included in the plurality of rule data structures.
 11. A system according to claim 10, further comprising means for displaying the graphic and a plurality of region indicators, each region indicator being superimposed on a respectively different one of the plurality of regions.
 12. A system according to claim 10, further comprising means for generating and transmitting a message which identifies a number of regions in the plurality of regions, and the region identifier, the visual attribute value, and the position coordinates stored in each region data structure.
 13. A system according to claim 10, further comprising means for dynamically selecting a subset of the plurality of regions for which the value of the visual attribute is determined using the rule.
 14. A system for managing a plurality of data values which define an attribute of an object, comprising:(a) a computer having a display and including a user defined database which stores the data values; (b) means for defining an arbitrary, user defined graphic as a bitmap that is displayed by the computer; (c) means for identifying a plurality of regions within the graphic, each region being associated with a respective value which represents a visual attribute of the region, the identifying means including means for storing a graphic data structure which includes:(1) the bitmap; (2) a plurality of region data structures, including a region data structure for each respective region, each comprising:(A) a region identifier of the region, (B) a value of the visual attribute at a border of the region, and (C) a plurality of position coordinates defining a point in the region as a location in the graphic; (3) a plurality of rule data structures, each, comprising:(A) a rule which defines the value of the visual attribute as a function of an argument, (B) a rule identifier of the rule, (C) the argument of the rule, (D) a value which defines the argument by type, (E) an identifier of a database in which the plurality of data are stored, and (F) a query that is used to retrieve one of the data values from the database to be used as the value of the argument; (d) means for linking individual ones of the plurality of regions of the graphic to respective data fields of the database, each data field having one of the plurality of data values stored therein; and (e) means for automatically changing the visual attribute of each region, individually, in accordance with a respective one of the plurality of rules corresponding to the region, when the respective data value corresponding to the region changes.
 15. A computer-readable medium for use in a computer system having a display and including a user defined database management system or spread sheet which stores data, said computer readable medium being encoded with a computer program for managing a plurality of data which define attributes of vehicle tires, the data including at least one of the group consisting of tire tread depth data and tire age data, the computer-readable medium comprising:means for causing the computer to define and display an arbitrary, user defined graphic representing the object; region identifying means for causing the computer to identify a region within the graphic, and associate a value with the region, the value representing a visual attribute, wherein the region identifying means include a region data structure for the region, the region data structure comprising:a region identifier, a value of the visual attribute at a border of the region, and a plurality of position coordinates defining a location of a point in the region; means for causing the computer to link the identified region of the graphic to a data field of the database or spreadsheet, the data field having one of the plurality of data values stored therein; means for causing the computer to apply a rule to determine the value of the visual attribute as a function of the one data value stored in the data field; and means for causing the computer to automatically change the visual attribute of the region in accordance with the rule when the one data value changes.
 16. A computer-readable medium for use in a computer system having a display and including a user defined database management system or spread sheet which stores data, said computer readable medium being encoded with a computer program for managing a plurality of data which define attributes of vehicle tires, the data including at least one of the group consisting of tire tread depth data and tire age data, the computer-readable medium comprising:means for causing the computer to define and display an arbitrary, user defined graphic representing the object; means for causing the computer to identify a region within the graphic and associate a value with the region, the value representing a visual attribute; means for causing the computer to link the identified region of the graphic to a data field of the database or spreadsheet, the data field having one of the plurality of data values stored therein; rule applying means for causing the computer to apply a rule to determine the value of the visual attribute as a function of the one data value stored in the data field, wherein the rule applying means includes a rule data structure comprising:a rule identifier of the rule, at least one argument having a value, a value which defines the argument by type, an identifier of a database in which the plurality of data are stored, a query that is used to retrieve the one data value from the database for use as the value of the argument, and the rule, wherein the rule defines the value of the visual attribute as a function of the value of the argument, and means for causing the computer to automatically change the visual attribute of the region in accordance with the rule when the one data value changes. 